LINC01635, a long non-coding RNA with a cancer/testis expression pattern, promotes lung cancer progression by sponging miR-455-5p.

Long non-coding RNAs (lncRNAs) have been reported to play vital roles in human lung cancer. In recent years, cancer/testis (CT) lncRNAs have been characterized as a novel class of lncRNA. However, this class of lncRNA remains to be thoroughly investigated. The present study identified long intergenic non-protein coding RNA 1635 (LINC01635), which was highly expressed in testis and in a broad range of human cancer types. Next, it was confirmed that LINC01635 was upregulated significantly in samples from patients with lung cancer and in non-small cell lung carcinoma (NSCLC) cell lines. Silencing LINC01635 suppressed the proliferation and metastasis of NSCLC cells in vitro and in vivo. Furthermore, it was found that LINC01635 could bind to microRNA (miRNA or miR)-455-5p and regulate the expression of a series of miR-455-5p-targeting tumor-related genes. Knockdown of miR-455-5p partially rescued the progression of lung cancer cells that was suppressed by LINC01635 silencing. Together, the current results demonstrated that LINC01635 may play important roles in NSCLC progression by targeting miR-455-5p, and that it could be a biomarker and therapeutic target for lung cancer.

Direct Measuring Particulate Matters in Smoke Plumes from Chimneys in a Textile Dyeing Industrial Park by a Self-Developed PM Detector on an UAV in Yangtze River Delta of China.

Directly measuring particulate matters (PM) from chimneys in an industrial park is difficult due to it being hard to reach the peak heights. A self-developed PM detector on an unmanned aerial vehicle (UAV) had been deployed to directly measure the PM emissions in smoke plumes from chimneys in a textile dyeing industrial park. Compared with a commercial PM device (LD-5R, SIBATA, Kyoto, Japan), the self-developed detector showed similar performance with a good correlation (R2 varying from 0.911 to 0.951) in simultaneously vertical PM measurements on UAV. The PM emissions from chimneys after different textile treating processes, including pigment printing, dyeing process, and digital printing, were investigated. PM mass concentrations and particle number concentrations (PNC) in different sizes were found to be significantly higher in pigment printing than those in dyeing process and digital printing by 2 or 3 times after electrostatic precipitation. The activated carbon adsorption and electrostatic precipitation were the major PM controlling techniques in the park. The PM mass concentrations and PNC were the highest in the process of dyeing after activated carbon adsorption with the concentrations of PM1 (1000 µg·m-3), PM2.5 (1600 µg·m-3), and PM10 (2000 µg·m-3), respectively. According to the results of PM and PNC, PM2.5 was found to be the dominant particles accounting for 99% of the PM emissions. It may be due to the high temperature in thermo-fixing machine, which is beneficial to the PM2.5 generation. This study revealed PM2.5 was the dominant particles to be reduced in textile dyeing enterprises to mitigate PM pollution.

Engineering multiscale polypyrrole/carbon nanotubes interface to boost electron utilization in a bioelectrochemical system coupled with chemical absorption for NO removal.

The chemical absorption-bioelectrochemical reduction (CABER) integrated system provides an alternative of good potential for NO removal. The efficient utilization of cathode electrons directly determines the system performance and operating cost. Herein, we synthesize a polypyrrole/carbon nanotubes (PPy/CNTs) composite to engineer a micro-and nanoscale interface with low resistance and high biocompatibility between the cathode and biofilms in the CABER system. The resulting PPy/CNTs biocathodes exhibit 36.4% increase in biomass density, 40.7%-302.6% increase in Faraday efficiency along Fe(III)EDTA reduction, and 204% increase in Fe(II)EDTA-NO reduction rate. The enrichment of functional microorganisms is validated to be a key strengthening factor, as the proportion of which increased from 57.9% to 84.6%. Moreover, for efficient electron transfer and utilization, a low-resistance electron transfer route, "electrode substrate → PPy (→ CNTs) → microbial cells → Fe(III)EDTA or Fe(II)EDTA-NO", is realized in the multiscale conductive networks constructed of PPy/CNTs composite and microbial nanowires.

Clinical pharmacology considerations for the approval of belimumab for the treatment of adult patients with active lupus nephritis: A regulatory perspective.

On 16 December 2020, FDA approved Benlysta® (belimumab) for both the intravenous (IV) and subcutaneous (SC) administration routes for the treatment of adult patients with active lupus nephritis (LN) who are receiving standard therapy. This approval represents the first FDA approved treatment of patients with active LN.The approved IV dosing regimen (10 mg/kg dose Q2W for three doses, then 10 mg/kg Q4W thereafter) was based on a randomized double-blind placebo controlled clinical trial in adult patients with LN. For the approval of the SC dosing regimen (400 mg dose QW for four doses, then 200 mg QW thereafter), efficacy was supported solely by pharmacokinetics (PK) modeling and simulation which estimated a matched steady state average concentration and higher trough concentrations for the SC administration route, for bridging to the efficacy of IV belimumab in adults with LN. The safety and immunogenicity profile of the SC administration route has been assessed in the SLE studies.In a population PK analysis, higher proteinuria was associated with greater belimumab clearance and lower belimumab exposure. In an exposure response analysis, the efficacy of belimumab as evaluated by renal response was mainly driven by patients with lower proteinuria at baseline regardless of other baseline characteristics (e.g. baseline renal function, renal biopsy classification), induction therapies, or belimumab exposure levels (within 10 mg/kg dosing regimen), etc. However, post hoc analyses showed that belimumab had activity in LN patients with higher proteinuria at baseline. There is no adequate information to suggest that a higher dose would provide additional benefit for patients with lower exposure (e.g. higher proteinuria).

Interaction of tetrahydrofuran and methyl tert-butyl ether in waste gas treatment by a biotrickling filter bioaugmented with Piscinibacter caeni MQ-18 and Pseudomonas oleovorans DT4.

Bioaugmented biotrickling filter (BTF) seeded with Piscinibacter caeni MQ-18, Pseudomonas oleovorans DT4, and activated sludge was established to investigate the treatment performance and biodegradation kinetics of the gaseous mixtures of tetrahydrofuran (THF) and methyl tert-butyl ether (MTBE). Experimental results showed an enhanced startup performance with a startup period of 9 d in bioaugmented BTF (25 d in control BTF seeded with activated sludge). The interaction parameter I2,1 of control (7.462) and bioaugmented BTF (3.267) obtained by the elimination capacity-sum kinetics with interaction parameter (EC-SKIP) model indicated that THF has a stronger inhibition of MTBE biodegradation in the control BTF than in the bioaugmented BTF. Similarly, the self-inhibition EC-SKIP model quantified the positive effects of MTBE on THF biodegradation, as well as the negative effects of THF on MTBE biodegradation and the self-inhibition of MTBE and THF. Metabolic intermediate analysis, real-time quantitative polymerase chain reaction, biofilm-biomass determination, and high-throughput sequencing revealed the possible mechanism of the enhanced treatment performance and biodegradation interactions of MTBE and THF.

Mass transfer and reaction simultaneously enhanced airlift microbial electrolytic cell system with high gaseous o-xylene removal capacity.

To overcome the limitation of mass transfer and reaction rate involved in the biodegradation of gaseous o-xylene, the airlift reactor and microbial electrolysis cell were integrated to construct an airlift microbial electrolysis cell (AL-MEC) system for the first time, in which the bioanode was modified by polypyrrole to further improve biofilm attachment. The developed AL-MEC system achieved 95.4% o-xylene removal efficiency at optimized conditions, and maintained around 75% removal efficiency even while the inlet o-xylene load was as high as 684 g m-3 h-1. The existence of O2 exhibited a competition in electrons with the bioanode but a positive effect on ring-opening process in the o-xylene oxidation. The limitation of mass transfer had been overcome as the empty bed resistance time in the range of 20-80 s did not influence the system performance significantly. The microbial community analysis confirmed the o-xylene degradation microbes and electroactive bacteria were the dominant, which could be further enriched at 0.3 V against standard hydrogen electrode. This work revealed the feasibility of the AL-MEC system for the degradation of o-xylene and similar compounds, and provided insights into bioelectrochemical system design with high gaseous pollution removal capacity.

Heterologous expression of bacterial cytochrome P450 from Microbacterium keratanolyticum ZY and its application in dichloromethane dechlorination.

Dichloromethane (DCM) is a volatile halogenated hydrocarbon with teratogenic, mutagenic and carcinogenic effects. Biodegradation is generally regarded as an effective and economical approach of pollutant disposal. In this study, a novel strain was isolated and its cytochrome P450 was heterologously expressed for DCM degradation. The isolate, Microbacterium keratanolyticum ZY, was characterized as a Gram-positive, rod-shaped and flagella-existed bacterium without spores (GenBank No. SUB8814364; CCTCC M 2019953). After successive whole-genome sequencing, assembly and annotation, eight identified functional genes (encoding cytochrome P450, monooxygenase, dehalogenase and hydrolase) were successfully cloned and expressed in Escherichia coli BL21 (DE3). The recombinant strain expressing cytochrome P450 presented the highest degradation efficiency (90.6%). Moreover, the specific activity of the recombinant cytochrome P450 was more than 1.2 times that of the recombinant dehalogenase (from Methylobacterium rhodesianum H13) under their optimum conditions. The kinetics of DCM degradation by recombinant cytochrome P450 was well fitted with the Haldane model and the value of maximum specific degradation rate was determined to be 0.7 s-1. The DCM degradation might occur through successive hydroxylation, dehydrohalogenation, dechlorination and oxidation to generate gem-halohydrin, formyl chloride, formaldehyde and formic acid. The study helps to comprehensively understand the DCM dechlorination process under the actions of bacterial functional enzymes (cytochrome P450 and dehalogenase).

A disease progression model of longitudinal lung function decline in idiopathic pulmonary fibrosis patients.

Pirfenidone and nintedanib are the first two FDA-approved therapies for treatment of idiopathic pulmonary fibrosis (IPF). The clinical programs for pirfenidone and nintedanib included 1132 patients in the placebo arms and 1691 patients in the treatment arms across 6 trials. We developed a disease progression model to characterize the observed variability in lung function decline, measured as percent predicted forced vital capacity (%p-FVC), and its decrease in decline after treatment. The non-linear longitudinal change in %p-FVC was best described by a Weibull function. The median decreased decline in %p-FVC after treatment was estimated to be 1.50% (95% CI [1.12, 1.79]) and 1.96% (95% CI [1.47, 2.36]) at week 26 and week 52, respectively. Smoking status, weight, %p-FVC, %p-DLco and oxygen use at baseline were identified as significant covariates affecting decline in %p-FVC. The decreased decline in %p-FVC were observed among all subgroups of interest, of which the effects were larger at 1 year compared to 6 months. Based on the disease progression model smoking status and oxygen use at baseline may affect the treatment effect size. At week 52, the decreased decline in %p-FVC for current smokers and patients with oxygen use at baseline were 1.56 (90% CI [1.02, 1.99]) and 2.32 (90% CI [1.74, 2.86]), respectively. These prognostic factors may be used to enrich studies with patients who are more likely to respond to treatment, by demonstrating a lesser decline in lung function, and therefore provide the potential to allow for IPF studies with smaller study populations or shorter durations.

Characteristics and removal of microplastics in rural domestic wastewater treatment facilities of China.

The environment of the countryside is different from that of the city. Studying the abundance, characteristics, and removal of microplastics (MPs) in rural domestic wastewater treatment facilities (RD-WWTFs) is of great significance for understanding the impacts of human activities on the environment of the countryside. Therefore, we studied five such facilities in the Hangzhou region of China. The abundance of MPs in the influent was 430-2154 items/m3. Micro-Raman spectroscopic analysis indicates that the main type of polymer in the influent is polypropylene (PP, 54.6%), followed by polystyrene (PS, 29.7%) and polyethylene terephthalate (PET, 9.7%). The color of MPs is mainly white and clear (62.9%), red (13.3%) and gray (12.0%). Our results show that fragments (71.3%) are the dominant shape of MPs, followed by fibers (21.5%). The characteristics of MPs, such as sizes, shapes, and types, along with the treatment process, affect the removal of MPs in RD-WWTFs. Large MPs are easily removed by anaerobic processes, while small MPs are better removed by anaerobic/anoxic/oxic processes. Fibrous MPs are more difficult to be removed than the fragmented ones. Constructed wetlands play an important role in the removal of MPs.

Enhanced denitrification performance of Alcaligenes sp. TB by Pd stimulating to produce membrane adaptation mechanism coupled with nanoscale zero-valent iron.

The microbial reduction of nitrate in the presence of nanoscale zero-valent iron (nZVI) was evaluated to assess the feasibility of employing nZVI for biological denitrification treatment. The effect of modified nZVI on the growth, metabolism, and denitrification performance of Alcaligenes sp. TB under aerobic conditions was studied. Results showed that Alcaligenes sp. TB with nZVI/Pd had 31.5% increase in nitrate removal and 18.1% decrease in nitrite accumulation within 28 h. nZVI/Pd exhibited less inhibition on the cell growth (OD600 = 0.725), NADH/NAD+ ratio (86% of control), and electron transfer system activity (68.5% of control). In addition, nZVI/Pd decreased the membrane fluidity by increasing the trans/cis isomerization ratio (317.7% of control) to enhance the resistance of nZVI. This study underlines the effects of nZVI/Pd on membrane susceptibility via membrane fatty acid transformation during denitrification and suggests the influence of engineered nanomaterials on denitrification.

Reduction of FeII(EDTA)-NO by Mn powder in wet flue gas denitrification technology: stoichiometry, kinetics, and thermodynamics.

Conversion of FeII(EDTA)-NO or FeIII(EDTA) into FeII(EDTA) is a key process in a wet flue gas denitrification technology with FeII(EDTA) solution. In this work, the stoichiometry, kinetics, and thermodynamics of FeII(EDTA)-NO reduction by Mn powder were investigated. We first studied the FeII(EDTA)-NO reduction and product distribution to speculate a possible stoichiometry of FeII(EDTA)-NO reduction by Mn powder. Then, the effects of major influencing factors, such as pH value, temperature, and Mn concentration, were studied. The pseudo-second-order model was established to describe the FeII(EDTA)-NO reduction. Simultaneously, according to Arrhenius and Eyring-Polanyi equations, the reaction activation energy (Ea), enthalpy of activation (∆H‡), and entropy of activation (∆S‡) were calculated as 23.68 kJ/mol, 21.148 kJ/mol, and - 149.728 J/(k mol), respectively. Additionally, simultaneous reduction of FeIII(EDTA) and FeII(EDTA)-NO was investigated to better study the mechanism of FeII(EDTA) regeneration, suggesting that there was a competition between the two reduction processes. Finally, a simple schematic mechanism of NO absorption by FeII(EDTA) combined with regeneration of manganese ion and ammonium was proposed. These fundamental researches could offer a valuable guidance for wet flue gas denitrification technology with FeII(EDTA) solution.

Enhancing Chlorobenzene Biodegradation by Delftia tsuruhatensis Using a Water-Silicone Oil Biphasic System.

In this study, a water-silicone oil biphasic system was developed to enhance the biodegradation of monochlorobenzene (CB) by Delftia tsuruhatensis LW26. Compared to the single phase, the biphasic system with a suitable silicone oil fraction (v/v) of 20% allowed a 2.5-fold increase in the maximum tolerated CB concentration. The CB inhibition on D. tsuruhatensis LW26 was reduced in the presence of silicone oil, and the electron transport system activity was maintained at high levels even under high CB stress. Adhesion of cells to the water-oil interface at the water side was observed using confocal laser scanning microscopy. Nearly 75% of cells accumulated on the interface, implying that another interfacial substrate uptake pathway prevailed besides that initiated by cells in the aqueous phase. The 8-fold increase in cell surface hydrophobicity upon the addition of 20% (v/v) silicone oil showed that silicone oil modified the surface characteristics of D. tsuruhatensis LW26. The protein/polysaccharide ratio of extracellular polymeric substances (EPS) from D. tsuruhatensis LW26 presented a 3-fold enhancement. These results suggested that silicone oil induced the increase in the protein content of EPS and rendered cells hydrophobic. The resulting hydrophobic cells could adhere on the water-oil interface, improving the mass transfer by direct CB uptake from silicone oil.

Dosage Considerations for Canakinumab in Children With Periodic Fever Syndromes.

Periodic fever syndromes are a group of rare diseases with a highly variable onset, yet limited treatment options are available for children at an early age. Canakinumab has been approved to treat patients with cryopyrin-associated periodic syndrome, a periodic fever syndrome, and systemic juvenile systemic arthritis, with age cutoffs of 4 years and 2 years, respectively. In 2016, the US Food and Drug Administration (FDA) approved canakinumab, without an age restriction, for the treatment of three conditions of periodic fever syndromes, including familial Mediterranean fever, hyperimmunoglobulin D syndrome/mevalonate kinase deficiency, and tumor necrosis factor receptor-associated periodic syndrome. This review discusses the pharmacokinetic (PK), efficacy, safety, and exposure-response relationship of canakinumab and provides the rationale for dosage recommendation in children younger than 2 years of age with the three conditions of periodic fever syndromes. The approval of canakinumab for these pediatric patients addresses a critical unmet medical need.

[Treatment of the Waste Gas Containing Methyl tert-Butyl Ether via a Biotrickling Filter].

The performance and microbial communities of methyl tert-butyl ether (MTBE) treatment using a biotrickling filter (BTF) that was inoculated with activated sewage sludge were investigated. The BTF successfully started up within 23 days when the inlet concentration of MTBE was 100 mg·m-3 and empty bed retention time was 60 s, with 70% removal efficiency (RE). Under steady-state conditions, an elimination capacity (EC) and a mineralization ratio of 13.47 g·(m3·h)-1 and 68% were achieved, respectively. The ECmax was 21.03 g·(m3·h)-1 according to the Haldane model, and a KS of 0.16 g·m-3 and KI of 0.99 g·m-3 were obtained. High-throughput sequencing was used to identify the community structure of the mixed microbial consortium in the BTF. The results indicated that Methylibium sp. (11.33%) and Blastocatella sp. (9.95%) were the dominant bacteria.

Piscinibacter caeni sp. nov., isolated from activated sludge.

A yellowish-pigmented bacterial strain, designated as MQ-18T, was isolated from a sample of activated sludge collected from a pharmaceutical factory in Zhejiang, China. The strain was characterized through a polyphasic taxonomy approach. 16S rRNA gene sequence analysis demonstrated that strain MQ-18T showed high similarities to Piscinibacter defluvii SH-1T (99.7 %) and Piscinibacter aquaticus IMCC1728T (98.4 %), thereby suggesting that it belongs to the genus Piscinibacter. The DNA-DNA relatedness values of this strain to strains SH-1T and IMCC1728T were only 35.4 and 33.3 %, respectively. Cells of MQ-18T were Gram-negative, aerobic, motile, rod-shaped and non-spore forming. This strain exhibited growth at 25-37 °C (optimum: 30 °C) in the presence of 0-3.0 % (w/v) NaCl (optimum, 0 % NaCl) and at pH 5.0-8.0 (pH 7.0). The predominant fatty acids were C12 : 0 (5.5 %), C16 : 0 (33.7 %), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c; 38.5 %), and summed feature 4 (anteiso-C17 : 1 B and/or iso C17 : 1 I; 11.6 %). The main quinone type was ubiquinone-8, and the major polyamines were cadaverine and putrescine. The major polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The DNA G+C content was 70.1 mol%. On the basis of its phylogenetic, phenotypic and physiological characteristics, strain MQ-18T is considered to represent a novel species of the genus Piscinibacter, for which the name Piscinibacter caeni sp. nov. is proposed. The type strain is MQ-18T (CCTCC AB 2017223T=JCM 32138T).

Kinetics, Thermodynamics, and Mechanism of a Novel Biphasic Solvent for CO2 Capture from Flue Gas.

The main issue related to the deployment of the amine-based absorption process for CO2 capture from flue gas is its intensive energy penalty. Therefore, this study screened a novel biphasic solvent, comprising a primary amine e.g., triethylenetetramine (TETA) and a tertiary amine e.g., N, N-dimethylcyclohexylamine (DMCA), to reduce the energy consumption. The TETA-DMCA blend exhibited high cyclic capacity of CO2 absorption, favorable phase separation behavior, and low regeneration heat. Kinetic analysis showed that the gas- and liquid-side mass transfer resistances were comparable in the lean solution of TETA-DMCA at 40 °C, whereas the liquid-side mass transfer resistance became dominant in the rich solution. The rate of CO2 absorption into TETA-DMCA (4 M, 1:3) solution was comparable to 5 M benchmark monoethanolamine (MEA) solution. Based on a preliminary estimation, the regeneration heat with TETA-DMCA could be reduced by approximately 40% compared with that of MEA. 13C NMR analysis revealed that the CO2 absorption into TETA-DMCA was initiated by the reaction between CO2 and TETA via the zwitterion mechanism, and DMCA served as a CO2 sinker to regenerate TETA, resulting in the transfer of DMCA from the upper to lower phase. The proposed TETA-DMCA solvent may be a suitable candidate for CO2 capture.

Determination of hexachlorobutadiene, pentachlorobenzene, and hexachlorobenzene in waste incineration fly ash using ultrasonic extraction followed by column cleanup and GC-MS analysis.

Hexachlorobutadiene (HCBD) was listed as a new controlling persistent organic pollutant in the Stockholm Convention because of its wide industrial applications and potential genotoxicity and carcinogenicity. However, only limited information exists on the release of HCBD from unintentional sources, such as waste incineration. Identification and quantification of HCBD in fly ash, one of the major outputs of waste incineration, is imperative. This work presents a simple method for determining HCBD in waste incineration fly ash based on ultrasonic extraction coupled with a silica gel-Florisil column cleanup followed by gas chromatography-mass spectrometry detection. Two typical persistent organic pollutants, pentachlorobenzene (PeCB) and hexachlorobenzene (HCB), were measured simultaneously. The parameters that influence the extraction efficiency and the quality of instrument detection were studied. Under the optimum experimental conditions, high sensitivity (detection limit 0.25-0.53 ng g-1), acceptable recoveries (64.0-71.4%) at spiking levels of 5-500 ng g-1, and good repeatability [relative standard deviation (n = 3) of 14% or less] were achieved for all target analytes. The validation of this method was performed by analysis of six real fly ash samples from different waste incinerators in eastern China. The concentrations of HCBD detected in these samples (1.39-97.6 ng g-1) were comparable to those of PeCB (1.22-150 ng g-1) and HCB (0.82-120 ng g-1), indicating that the residual HCBD as well as PeCB and HCB in waste incineration fly ash should not be ignored. The results confirm for the first time that waste incineration is an unintentional source of HCBD in China. Graphical abstract An analytical method for hexachlorobutadiene, pentachlorobenzene, and hexachlorobenzene in fly ash from waste incineration. GC-MS gas chromatography-mass spectrometry, Ph-d10 phenanthrene-d10.

Drug Modulators of B Cell Signaling Pathways and Epstein-Barr Virus Lytic Activation.

Epstein-Barr virus (EBV) is a ubiquitous human gammaherpesvirus that establishes a latency reservoir in B cells. In this work, we show that ibrutinib, idelalisib, and dasatinib, drugs that block B cell receptor (BCR) signaling and are used in the treatment of hematologic malignancies, block BCR-mediated lytic induction at clinically relevant doses. We confirm that the immunosuppressive drugs cyclosporine and tacrolimus also inhibit BCR-mediated lytic induction but find that rapamycin does not inhibit BCR-mediated lytic induction. Further investigation shows that mammalian target of rapamycin complex 2 (mTORC2) contributes to BCR-mediated lytic induction and that FK506-binding protein 12 (FKBP12) binding alone is not adequate to block activation. Finally, we show that BCR signaling can activate EBV lytic induction in freshly isolated B cells from peripheral blood mononuclear cells (PBMCs) and that activation can be inhibited by ibrutinib or idelalisib.IMPORTANCE EBV establishes viral latency in B cells. Activation of the B cell receptor pathway activates lytic viral expression in cell lines. Here we show that drugs that inhibit important kinases in the BCR signaling pathway inhibit activation of lytic viral expression but do not inhibit several other lytic activation pathways. Immunosuppressant drugs such as cyclosporine and tacrolimus but not rapamycin also inhibit BCR-mediated EBV activation. Finally, we show that BCR activation of lytic infection occurs not only in tumor cell lines but also in freshly isolated B cells from patients and that this activation can be blocked by BCR inhibitors.

Characterization and Genome Analysis of a Nicotine and Nicotinic Acid-Degrading Strain Pseudomonas putida JQ581 Isolated from Marine.

The presence of nicotine and nicotinic acid (NA) in the marine environment has caused great harm to human health and the natural environment. Therefore, there is an urgent need to use efficient and economical methods to remove such pollutants from the environment. In this study, a nicotine and NA-degrading bacterium-strain JQ581-was isolated from sediment from the East China Sea and identified as a member of Pseudomonas putida based on morphology, physio-biochemical characteristics, and 16S rDNA gene analysis. The relationship between growth and nicotine/NA degradation suggested that strain JQ581 was a good candidate for applications in the bioaugmentation treatment of nicotine/NA contamination. The degradation intermediates of nicotine are pseudooxynicotine (PN) and 3-succinoyl-pyridine (SP) based on UV, high performance liquid chromatography, and liquid chromatography-mass spectrometry analyses. However, 6-hydroxy-3-succinoyl-pyridine (HSP) was not detected. NA degradation intermediates were identified as 6-hydroxynicotinic acid (6HNA). The whole genome of strain JQ581 was sequenced and analyzed. Genome sequence analysis revealed that strain JQ581 contained the gene clusters for nicotine and NA degradation. This is the first report where a marine-derived Pseudomonas strain had the ability to degrade nicotine and NA simultaneously.

Comparative investigation on a hexane-degrading strain with different cell surface hydrophobicities mediated by starch and chitosan.

Bioremediation usually exhibits low removal efficiency toward hexane because of poor water solubility, which limits the mass transfer rate between the substrate and microorganism. This work aimed to enhance the hexane degradation rate by increasing cell surface hydrophobicity (CSH) of the degrader, Pseudomonas mendocina NX-1. The CSH of P. mendocina NX-1 was manipulated by treatment with starch and chitosan solution of varied concentrations, reaching a maximum hydrophobicity of 52%. The biodegradation of hexane conformed to the Haldane inhibition model, and the maximum degradation rate (ν max) of the cells with 52% CSH was 0.72 mg (mg cell)-1·h-1 in comparison with 0.47 mg (mg cell)-1·h-1 for cells with 15% CSH. The production of CO2 by high CSH cells was threefold higher than that by cells at 15% CSH within 30 h, and the cumulative rates of O2 consumption were 0.16 and 0.05 mL/h, respectively. High CSH was related to low negative charge carried by the cell surface and probably reduced the repulsive electrostatic interactions between hexane and microorganisms. The FT-IR spectra of cell envelopes demonstrated that the methyl chain was inversely proportional to increasing CSH values, but proteins exhibited a positive effect to CSH enhancement. The ratio of extracellular proteins and polysaccharides increased from 0.87 to 3.78 when the cells were treated with starch and chitosan, indicating their possible roles in increased CSH.